The ideas of supply and demand, and philosophies concerning trade and the production and consumption of goods and services, are concepts that have existed since the dawn of mankind. As societies became more complex, however, people began to study these abstract concepts in a more formal way. The first recorded study of economics as a science, rather than a philosophical or political concept, was the book The Wealth of Nations by Scottish economist Adam Smith. This book represents the first attempt to fully analyze sources of income and the distribution of wealth. Smith's analysis of economics served as a guide by which many of the governmental economic policies of the present day were formed.